No. 4.] CHEMICAL AND FARM MANURES. 145 



phosphate find their way into the goods of certain fertilizer 

 companies, that it is no unimportant matter to the farmer 

 whether or not his land is acid and lacks carbonate of lime, 

 and is, therefore, in condition to make the best use of the 

 fertilizer which is applied. 



Before leaving this question, attention should be called to 

 the fact that all plants are not alike in their ability to utilize 

 mineral phosphates,* certain of the leguminosffi, according 

 to Prianichnikow, possessing this power in a much greater 

 degree than the cereals. Interesting and valuable data in 

 this connection have been obtained by Dietrich, in his study 

 of the action of various plants upon pulverized rock. That 

 various soils act differently as solvents of phosphates is a 

 matter of common scientific knowledge, though it has been 

 strikingly brought out by that veteran French chemist 

 Deherain, and by Prianichnikow. 



Realizing that it is the custom of some to present every- 

 thing to the farmer as settled fact, it may be a question if it 

 is not better to occasionally remove the screen, particularly 

 before a body of men like those in our audience to-day, and 

 show that those who have studied the question of phosphates 

 most deeply still have manifold problems to solve. It w^ould 

 seem to be important to call attention, also, to the necessity 

 of investigating not only the action of all kinds of plants 

 upon the difierent phosphates, but also the chemical character 

 and solvent action of soils themselves. Random compara- 

 tive trials of phosphates, reported without special reference 

 to the plants employed nor to the chemical reaction and 

 character of the soil, as is too frequently the case with those 

 who do not understand or appreciate the full significance 

 and bearing of these factors, are not calculated to result in 

 much of permanent value. It would seem important, there- 

 fore, that our progressive farmers should understand some- 

 thing of the intricacy and far-reaching import of such 

 inquiries, in order that they may have patience to wait for 

 results. So long as the community expects experiment 



* Compare Merrill, fourteenth Annual Report Maine Agricultural Experiment 

 Station (1888), p. 74 ; also Sclireiber, Revue General Agronomique, 1897, abstract in 

 Biedermann's Centralblatt 26, pp. 802-805; and Prianichnikow An. Agronomique 

 25, No. 4 (1899), pp. 177-187. 



